The maintenance of stromal integrity and hydration by epithelium-stroma and endothelium-stroma interactions will be studied. Epithelial mediated destruction of such stromal and basement membranous macromolecular elements as proteoglycosaminoglycans and collagen during and subsequent to induced traumas in animals and the development of pathological states in humans will be assessed by biochemical and biophysical measurements of catheptic and neutral protease activities in conjunction with electron microscopic evaluation. Characterization of potential proteolytic activities in the normal epithelium will provide a baseline for comparison. Suppression of enzyme activities by naturally occurring or exogenous inhibitors will be explored. Intemediary bioenergetic pathways will be investigated to ascertain the usefulness of the hexosemonophosphate shunt to transendothelial fluid transport. In vitro techniques will be employed to measure respiration of suitable corneal preparations in the presence of various combinations of such metabolic substrates as ascorbate, reduced and oxidized glutathione, adenosine and glucose under normal and reduced 02 availability.